How gangue particle size can affect the recovery of ultrafine and fine particles during froth flotation

In general, the poor flotation behavior of ultrafine (< 10 µm) particles is mainly associated with a low particle/bubble collision efficiency within the flotation process due to an unfavorable particle/bubble size ratio. In those considerations the size of the gangue particle system does not play a significant role. This study investigates the effect of gangue particle size on the recovery of ultrafine and fine (10…50 µm) particles. Artificial, binary model particle system, using magnetite as the target and quartz as the gangue mineral, are used for the investigation in order to considerably eliminate reported problems associated with ultrafine gangue particles. Results indicate that ultrafine magnetite can be recovered like fine magnetite when the gangue particles are fine as well. In contrast, fine magnetite recovery drops significantly when ultrafine quartz is used as the gangue mineral system.